Joystick Interposer cannot be detected as a controller device in Steam Proton/Wine and RPCS3

[Mengkzhaoyun]

the linux system joystick can detect gamepad
yuzu games can correct use gamepad , play totk is wonderful.

but the steam can not detect gamepad ， so many windows games , can not play with gamepad.
Is there a way to set some options make steam detect the gamepad?

selkies-gstreamer 1.6.0
use EGL Desktop in Docker

[Mengkzhaoyun]

the env set with lutris
export LD_PRELOAD='/usr/$LIB/selkies_joystick_interposer.so'
export SDL_JOYSTICK_DEVICE=/dev/input/js0

rpcs3 also can not detect the gamepad also with sdl mode.

[ehfd]

https://github.com/loochek/wine-vpad

Try installing the above to the Proton/Wine prefix (protontricks -c "wine PATH/TO/PROGRAM" APP_ID). More information at #55 (comment). Might have to reopen #55.

[Mengkzhaoyun]

Thanks for your guidance! I've developed a gamepad controller in Go using uinput, replacing the LD_PRELOAD solution. Now it works with both RPCS3 and Steam.
Because I'm using uinput, deployment requires additional privileges like adding the SYS_RAWIO capability and mounting the /dev/input directory. Uinput is really great, but it has some significant conflicts with our current solution. I can open-source the code if you're interested.

[ehfd]

We have previously replaced the uinput method in #95 with the LD_PRELOAD solution, closing #55 in the process.
We are reopening this issue because we had assumed that the LD_PRELOAD solution could replace all permutations of the uinput method.

CC @danisla

[danisla]

The LD_PRELOAD interposer library works by detecting open and ioctl syscalls and re-routing joystick events through a connected unix domain socket.
If the application isn't using direct /dev/input/jsX open calls it won't work.

Adding SDL and evdev interposition could make more applications, like RPCS3 work.
Hoping to find some time to work on this a bit more.

In the meantime, there are some improvements in #173 that fixes some other issues with applications that use epoll to get joystick input, namely Retroarch and possibly others.